fix: verify start state of a block

barretenberg/cpp/src/barretenberg/world_state/world_state.cpp

@@ -123,7 +123,7 @@ void WorldState::create_canonical_fork(const std::string& dataDir,
     }
     {
         uint32_t levels = _tree_heights.at(MerkleTreeId::ARCHIVE);
-        std::vector<bb::fr> initial_values{ compute_initial_archive(
+        std::vector<bb::fr> initial_values{ compute_initial_block_header_hash(
             get_state_reference(WorldStateRevision::committed(), fork, true), _initial_header_generator_point) };
         auto store = std::make_unique<FrStore>(
             getMerkleTreeName(MerkleTreeId::ARCHIVE), levels, _persistentStores->archiveStore);
@@ -876,9 +876,10 @@ bool WorldState::remove_historical_block(const block_number_t& blockNumber, Worl
     return true;
 }
 
-bb::fr WorldState::compute_initial_archive(const StateReference& initial_state_ref, uint32_t generator_point)
+bb::fr WorldState::compute_initial_block_header_hash(const StateReference& initial_state_ref, uint32_t generator_point)
 {
-    // NOTE: this hash operations needs to match the one in yarn-project/circuits.js/src/structs/header.ts
+    // NOTE: this hash operations needs to match the one in
+    // noir-project/noir-protocol-circuits/crates/types/src/block_header.nr
     return HashPolicy::hash({ generator_point,
                               // last archive - which, at genesis, is all 0s
                               0,

barretenberg/cpp/src/barretenberg/world_state/world_state.hpp

@@ -284,7 +284,7 @@ class WorldState {
     bool is_archive_tip(const WorldStateRevision& revision, const bb::fr& block_header_hash) const;
 
     bool is_same_state_reference(const WorldStateRevision& revision, const StateReference& state_ref) const;
-    static bb::fr compute_initial_archive(const StateReference& initial_state_ref, uint32_t generator_point);
+    static bb::fr compute_initial_block_header_hash(const StateReference& initial_state_ref, uint32_t generator_point);
 
     static StateReference get_state_reference(const WorldStateRevision& revision,
                                               Fork::SharedPtr fork,

barretenberg/cpp/src/barretenberg/world_state/world_state.test.cpp

@@ -184,6 +184,13 @@ TEST_F(WorldStateTest, GetInitialTreeInfoForAllTrees)
         EXPECT_EQ(info.meta.depth, tree_heights.at(MerkleTreeId::ARCHIVE));
         // this is the expected archive tree root at genesis
         EXPECT_EQ(info.meta.root, bb::fr("0x0237797d6a2c04d20d4fa06b74482bd970ccd51a43d9b05b57e9b91fa1ae1cae"));
+
+        // The leaf at index 0 is the genesis block hash.
+        assert_leaf_value(ws,
+                          WorldStateRevision::committed(),
+                          MerkleTreeId::ARCHIVE,
+                          0,
+                          fr("0x2da55666630fdf8594065c377958c827dc1c130dac91f17c6699b53dce60ef75"));
     }
 }
 

l1-contracts/src/core/Rollup.sol

@@ -149,7 +149,7 @@ contract Rollup is EIP712("Aztec Rollup", "1"), Ownable, Leonidas, IRollup, ITes
         congestionCost: 0
       }),
       archive: bytes32(Constants.GENESIS_ARCHIVE_ROOT),
-      blockHash: bytes32(0), // TODO(palla/prover): The first block does not have hash zero
+      blockHash: bytes32(Constants.GENESIS_BLOCK_HASH),
       slotNumber: Slot.wrap(0)
     });
     rollupStore.l1GasOracleValues = L1GasOracleValues({

l1-contracts/src/core/libraries/ConstantsGen.sol

@@ -93,6 +93,8 @@ library Constants {
   uint256 internal constant BLOBS_PER_BLOCK = 3;
   uint256 internal constant PRIVATE_LOG_SIZE_IN_FIELDS = 18;
   uint256 internal constant AZTEC_MAX_EPOCH_DURATION = 48;
+  uint256 internal constant GENESIS_BLOCK_HASH =
+    20646204262468251631976884937192820660867507115079672078981654411421834866549;
   uint256 internal constant GENESIS_ARCHIVE_ROOT =
     1002640778211850180189505934749257244705296832326768971348723156503780793518;
   uint256 internal constant FEE_JUICE_INITIAL_MINT = 200000000000000000000;

l1-contracts/src/core/libraries/RollupLibs/EpochProofLib.sol

@@ -200,9 +200,8 @@ library EpochProofLib {
       );
 
       bytes32 expectedPreviousBlockHash = _rollupStore.blocks[previousBlockNumber].blockHash;
-      // TODO: Remove 0 check once we inject the proper genesis block hash
       require(
-        expectedPreviousBlockHash == 0 || expectedPreviousBlockHash == _args[2],
+        expectedPreviousBlockHash == _args[2],
         Errors.Rollup__InvalidPreviousBlockHash(expectedPreviousBlockHash, _args[2])
       );
 

l1-contracts/test/fees/FeeRollup.t.sol

@@ -159,7 +159,7 @@ contract FeeRollupTest is FeeModelTestPoints, DecoderBase {
     // We will be using the genesis for both before and after. This will be impossible
     // to prove, but we don't need to prove anything here.
     bytes32 archiveRoot = bytes32(Constants.GENESIS_ARCHIVE_ROOT);
-    bytes32 blockHash = 0x267f79fe7e757b20e924fac9f78264a0d1c8c4b481fea21d0bbe74650d87a1f1;
+    bytes32 blockHash = bytes32(Constants.GENESIS_BLOCK_HASH);
 
     bytes32[] memory txHashes = new bytes32[](0);
     Signature[] memory signatures = new Signature[](0);